Rolling road results
Discussion
Went down to Peninsula on Friday to do the (hopefully) final set up on the Cosworth V6, and check the fueling/emissions on Steve Edmonds rolling road. Once Steve had set up the carbs, we did a couple of power runs and a speedo check. This was most interesting for me as I had never witnessed a rolling road session. Sitting on the boot to stop the wheelspin while Steve wound the car up to 5500rpm in 5th(imposed by me as we weren't sure if the engine was equipped with a rev limiter) was an initially scary and very loud experience!
The results were pretty gratifying:
RPM BHP at wheels
2000 68
2500 88
3000 110
3500 138
4000 155
4500 170
5000 190
5500 174
Steve said that the losses through the transmission would indicate that the engine was pushing out an equivalent 240 ish BHP at the flywheel. Stupidly I forgot to ask for the torque figures, but I will get them tomorrow, so will edit this when I have same.
There was a certain amount of surprise at the BHP output at low RPM,s as we had all assumed that the revised cam profile would make the engine less tractable than it appears to be. Having driven the car for 300 ish miles since the transplant, I am quite pleased with the 'drivability' for normal road use, as it is perfectly possible to pootle around at revs less than 3000 with reasonable economy. Don't know what extended high speeds will do yet, but as I'm off to Germany in a couple of weeks I'll probably find out
Btw the speedo check proved that the S speedo was out by about 10% and was pretty linear all the way from 30 to 100. As his parting shot Steve introduced an amount of resistance to simulate road conditions and accelerated the car from 0 to maximum in 5th (5500rpm)which proved to be 155mph.
Cheers
Graham
The results were pretty gratifying:
RPM BHP at wheels
2000 68
2500 88
3000 110
3500 138
4000 155
4500 170
5000 190
5500 174
Steve said that the losses through the transmission would indicate that the engine was pushing out an equivalent 240 ish BHP at the flywheel. Stupidly I forgot to ask for the torque figures, but I will get them tomorrow, so will edit this when I have same.
There was a certain amount of surprise at the BHP output at low RPM,s as we had all assumed that the revised cam profile would make the engine less tractable than it appears to be. Having driven the car for 300 ish miles since the transplant, I am quite pleased with the 'drivability' for normal road use, as it is perfectly possible to pootle around at revs less than 3000 with reasonable economy. Don't know what extended high speeds will do yet, but as I'm off to Germany in a couple of weeks I'll probably find out
Btw the speedo check proved that the S speedo was out by about 10% and was pretty linear all the way from 30 to 100. As his parting shot Steve introduced an amount of resistance to simulate road conditions and accelerated the car from 0 to maximum in 5th (5500rpm)which proved to be 155mph.
Cheers
Graham
. Richard Smith (Peninsula) thought the conversion was about as quick as a V8S, and I thought they produced similar o/p's, so don't worry Harry. I too will be interested in the torque figures, but I don't expect a V6 to come close to a V8 in the 'low down grunt' department, but then I like changing gear
Cheers
Graham
Cheers
Graham
Graham
I don’t doubt that the Cossie has more power than the lugging V8 but I just looked at those figures again
to go from 190 at the wheels onto an estimated 240(ish) at the flywheel would put the losses at over 25% 
.
Did the road itself not calculate these figures
as when I had a quick go in mine she put out around 175 at the wheels (with a wheel spin they couldn't keep under control 
) the wind down calculation of the machine gave a figure of 208, which is around 18% losses .
Either way you have some impressive figures there, interesting how it tails off at 5500 almost like a big V8
.
Harry
I don’t doubt that the Cossie has more power than the lugging V8 but I just looked at those figures again
to go from 190 at the wheels onto an estimated 240(ish) at the flywheel would put the losses at over 25% . Did the road itself not calculate these figures
as when I had a quick go in mine she put out around 175 at the wheels (with a wheel spin they couldn't keep under control ) the wind down calculation of the machine gave a figure of 208, which is around 18% losses . Either way you have some impressive figures there, interesting how it tails off at 5500 almost like a big V8
. Harry
Harry
I agree that the losses seem high, but I am only going on what the Steve said was correct for his r/r. As we both know the 'at the flywheel' figure is questionable at best, but I have no reason to doubt the 'at the wheel' figures.
As to wheelspin, there were two 'pie friendly' gentlemen sitting on the boot, with Steve and one of his lads in the car, and we were still getting w/spin
Your 208 calc seems low for a 4.0 HC, as I thought they put out more like 240. What did surprise everyone were the outputs at low RPM, and having graphed the torque curve it seems pretty flat all the way from 2000 to 5500
rpm lb/ft at wheels
2000 179
2500 185
3000 193
3500 207
4000 204
4500 198
5000 197
5500 166
I don't know what the Cosworth will rev to, but I can't see much point in changing gear above 5500
Cheers
Graham
>> Edited by gbgaffer on Monday 17th February 16:02
I agree that the losses seem high, but I am only going on what the Steve said was correct for his r/r. As we both know the 'at the flywheel' figure is questionable at best, but I have no reason to doubt the 'at the wheel' figures.
As to wheelspin, there were two 'pie friendly' gentlemen sitting on the boot, with Steve and one of his lads in the car, and we were still getting w/spin
Your 208 calc seems low for a 4.0 HC, as I thought they put out more like 240. What did surprise everyone were the outputs at low RPM, and having graphed the torque curve it seems pretty flat all the way from 2000 to 5500
rpm lb/ft at wheels
2000 179
2500 185
3000 193
3500 207
4000 204
4500 198
5000 197
5500 166
I don't know what the Cosworth will rev to, but I can't see much point in changing gear above 5500
Cheers
Graham
>> Edited by gbgaffer on Monday 17th February 16:02
GbGaffer,
How much did Richard charge to have the rolling road session at Peninsula ? Was wondering as toying with the idea of getting the V8S done at the next service just to see if it's performing as it should be ...still scares the sh.. out of me but if i get can get a few bhp more...
Cheers,
Ian
How much did Richard charge to have the rolling road session at Peninsula ? Was wondering as toying with the idea of getting the V8S done at the next service just to see if it's performing as it should be
...still scares the sh.. out of me but if i get can get a few bhp more... Cheers,
Ian
gbgaffer said: Harry
............
Your 208 calc seems low for a 4.0 HC, as I thought they put out more like 240. .........
I know but apparently it's not bad either, with 195/200 being fairly noraml for a 4.0 and 210 for a HC. I've subsequently learned than my cam maybe a bit tired (tappety) and the compressions whilst even across the board and are not bad but they are down slightly from a new engine.
Problem now being to get the cam sorted and the compression up (hopefully just valve leakage) i'd be looking at £600-800, considering it's not actually that far off the correct figures power wise I'll leave alone for the moment.
Toyed with the idea of going sprinting this year and wanted to stick to standard class, but if I go down the road of getting the heads off and cam changed it'll be rude not to get it tweaked at the same time, if you know what I mean
. Problem then being your then at the £2K mark, for not a lot more than that I could probably go down a standard 4.6 'long engine' with wilder cam route.........where does it all end. So as you see, to quote shpub
you may as well buy a griff500 Harry
Ian
I don't know what Richard would charge, as he hasn't billed me yet The Rolling Road is not Penininsula's but at 'Steve Edmond Motorsport' - a couple of miles up the road from Peninsula. I believe Richard puts a lot of work their way, so there may be some arrangement between them. You could always give Steve a call (01884 266243) and see what he would charge for a 'power run'. In my case we were using the r/r diagnostics & Steve's expertise to set up the carbs correctly.
Cheers
Graham
>> Edited by gbgaffer on Monday 17th February 19:16
I don't know what Richard would charge, as he hasn't billed me yet
The Rolling Road is not Penininsula's but at 'Steve Edmond Motorsport' - a couple of miles up the road from Peninsula. I believe Richard puts a lot of work their way, so there may be some arrangement between them. You could always give Steve a call (01884 266243) and see what he would charge for a 'power run'. In my case we were using the r/r diagnostics & Steve's expertise to set up the carbs correctly. Cheers
Graham
>> Edited by gbgaffer on Monday 17th February 19:16
Graham, My God your car is loud .. just spent the day at peninsula.
Incidently that V6 Cosworth lump is a beast .. My 4 litre V8 only pushes 202 @5000 rpm on the same rolling road. we edidnt get a 5500 and 6000 figure as we were in a hurry.
Incidently, the flywheel figure we calculated fo rthe old Rover V8 was 277bhp ( 75bhp lost through transmission ). that is spot on with TVR's recommended figures.
Jason
V8 Wedge
>> Edited by jvaughan on Tuesday 18th February 21:53
Blimey Jason what have you done since the last rolling road session recorded on here www.pistonheads.com/features/dyno.htm
Graham as you can see from this feature to have 200bhp at the wheels puts you in 500 country, then again it's a different RR, the one I used in stubbington is the same one/type as Power engineering have so my 175 doesn't seem too bad.
Maybe as you're local we could visit this as they do do a quite a bit of work for cossie engined cars as well.
It also proves that the AJP engine cars really do put out the power.
Harry
www.pistonheads.com/features/dyno.htm Graham as you can see from this feature to have 200bhp at the wheels puts you in 500 country, then again it's a different RR, the one I used in stubbington is the same one/type as Power engineering have so my 175 doesn't seem too bad
. Maybe as you're local we could visit this as they do do a quite a bit of work for cossie engined cars as well
. It also proves that the AJP engine cars really do put out the power.
Harry
Hi Jason/Harry
I am a little perturbed that you thought the S was loud Jason - this from But seriously Peninsula were supposed to be fitting the 'new' quieter exhaust yesterday - unless they were running the car without anything fitted!
Harry, yes I would be interested in visiting somewhere more local for a re-run in the near future, as I am not convinced that we've got the carb setup spot on yet. Do the people in Stubbington speak Weber?
Cheers
Graham
I am a little perturbed that you thought the S was loud Jason - this from
Jason "Large Bore 4-inches of Tail Pipe" Vaughan
But seriously Peninsula were supposed to be fitting the 'new' quieter exhaust yesterday - unless they were running the car without anything fitted! Is your V8 standard Jason? If so we've obviously got some more work to do on the S
.. My 4 litre V8 only pushes 202 @5000 rpm on the same rolling road
Harry, yes I would be interested in visiting somewhere more local for a re-run in the near future, as I am not convinced that we've got the carb setup spot on yet. Do the people in Stubbington speak Weber?
Cheers
Graham
Graham heres their details http://archive.scoot.co.uk/efi_diagnostics_performance/
When I went they were not totally aufait with the injected TVR rover V8 but if you want a RR check and a general health check they are good. I believe that the governor knows a bit about carb set ups as he's got a Westie Seight himself so I think that yours should be in the realms of their experience. There's a good pub down from there that the Hants TVRCC are going to in July which I'm helping arrange unfortunately I'm away on holiday at the time .
Harry
PS only 4" jason
When I went they were not totally aufait with the injected TVR rover V8 but if you want a RR check and a general health check they are good. I believe that the governor knows a bit about carb set ups as he's got a Westie Seight himself so I think that yours should be in the realms of their experience
. There's a good pub down from there that the Hants TVRCC are going to in July which I'm helping arrange unfortunately I'm away on holiday at the time . Harry
PS only 4" jason
Graham let me know if you book in I'd like to cpome along and kick the tyres.
re this sunday I think I'll be able to make this having just asked the gatekeeper , like you though, just for the meet at the ragged bear. Do you know what time that'll be graham.
Should be picking up the car tommorrow after it's week at the doctors so it'll be rude not check it out.
Shnozz maybe we could make it a 3 car 'S' bimble up the A32 to the meet what says thee
Harry
re this sunday I think I'll be able to make this
having just asked the gatekeeper , like you though, just for the meet at the ragged bear. Do you know what time that'll be graham. Should be picking up the car tommorrow after it's week at the doctors so it'll be rude not check it out
. Shnozz maybe we could make it a 3 car 'S' bimble up the A32 to the meet
what says thee Harry
Hi Harry/Shnozz
I don't get the car back until Saturday (bonnet being modded), but all being well, I'm up for a small convoy up to the meet. I will probably be staying in Hamble Saturday night, so could meet up somewhere convenient Sunday morning. As to time, I don't know what David has planned but I would think we should leave around 12:00. What think you?
Cheers
Graham
I don't get the car back until Saturday (bonnet being modded), but all being well, I'm up for a small convoy up to the meet. I will probably be staying in Hamble Saturday night, so could meet up somewhere convenient Sunday morning. As to time, I don't know what David has planned but I would think we should leave around 12:00. What think you?
Cheers
Graham
HarryW said: Blimey Jason what have you done since the last rolling road session recorded on here
Graham as you can see from this feature to have 200bhp at the wheels puts you in 500 country, then again it's a different RR, the one I used in stubbington is the same one/type as Power engineering have so my 175 doesn't seem too bad
Maybe as you're local we could visit this as they do do a quite a bit of work for cossie engined cars as well
It also proves that the AJP engine cars really do put out the power.
Harry
where can I start ?
Power Boost Valve calibrated for Max Fuel at Max Revvs ( Gives fantastic Pyrotechnics on overrun (4ft Flames when HOT!))
Ignition setup correctly, all Injectors cleaned, Air flow into engine bay has been smoothed (new air filter made a big difference !)
Standard Heads, but im running one of Richard Smiths US imported Wild Cams (more ferrocious than a 404 hybrid), stainless exhaust, with 4" tailpipe
Oh, and the fact the car is Driven rather than polished and left to rot in a garage
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